Hifiman EF600 Balanced Headphone Amplifier & DAC (HYMALAYA Pro R2R DAC) (Pre-Owned, Excellent Condition). I've run a variety of Hifiman headphones and others through this with no problems including: HE1000se, HE1000 Stealth, Ananda, Arya Organic, Sennheiser HD600, HD6XX, Dan Clark Ether Flow Open & Closed, Focal Clear/ Hadenys.
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